Advanced Metalworking Solutions for
Naval Systems that Go in Harm's Way

Grinding Swarf Reclamation and Reversion

Separating nickel alloy from grinding swarf will significantly reduce material costs for the F135 engine components. P&W image


The Navy Metalworking Center (NMC) is leading a Navy ManTech project that is developing a process to separate and recover nickel alloy from grinding swarf, enabling Pratt & Whitney (P&W) to revert the nickel alloy back into new forged billets. This will reduce the amount of virgin nickel material that needs to be procured, resulting in significant material cost savings for the F135 nickel components.


The Joint Strike Fighter (JSF) F135 engine turbine disks are made from virgin nickel superalloy forgings that are very expensive to produce. When the turbine disks are ground during fabrication, the swarf (material filings) that is generated contains the nickel alloy as well as cutting oil and ceramic media from the grinding disk. This contaminated by-product cannot be reverted into a new forged billet.

Technical Approach

The Integrated Project Team (IPT), consisting of the JSF Program Office, P&W, and NMC, will characterize the various constituents in the grinding swarf generated during the fabrication of the F135 turbine disks. The IPT will also identify the target specifications for the recovered nickel that will result in acceptable metal billets for reuse. The IPT will then conduct an industry survey of waste separation processes used to reclaim various materials, and NMC will lead lab-scale separation trials to develop a process to separate the nickel superalloy from the grinding swarf.


The project is expected to save at least $5,900 per engine, which equates to a five-year savings of $7M (1,188 engine sets). P&W further anticipates using the developed reversion process to recover material from other grinding swarf waste streams. This results in a total projected savings of $7.6M over five years, and $13.2M over the life of the program.


With industry support, the IPT will expand on the results from these trials to develop a grinding swarf separation process for use on a production scale. Once the production separation process has been successfully demonstrated, the team will produce a forged billet using the reclaimed nickel superalloy. The billet will be tested for concurrence with the applicable material specifications for the turbine disks.

Implementation is planned during fabrication of F135 nickel components at P&W in FY20.




Ken Koontz
F-35 Propulsion Acquisition Manager
JSF Program Office


Joint Strike Fighter Program Office
Pratt & Whitney